C++ Programming Code Examples
C++ > Recursion Code Examples
C++ program to Calculate Factorial of a Number Using Recursion
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/* C++ program to Calculate Factorial of a Number Using Recursion
Example to find factorial of a non-negative integer (entered by the user) using recursion.
This program takes a positive integer from user and calculates the factorial of that number. Suppose, user enters 6 then,
Factorial will be equal to 1*2*3*4*5*6 = 720
You'll learn to find the factorial of a number using a recursive function in this example.
In the above program, suppose the user inputs a number 6. The number is passed to the factorial() function.
In this function, 6 is multiplied to the factorial of (6 - 1 = 5). For this, the number 5 is passed again to the factorial() function.
Likewise in the next iteration, 5 is multiplied to the factorial of (5 - 1 = 4). And, 4 is passed to the factorial() function.
This continues until the value reaches 1 and the function returns 1.
Now, each function returns the value back to compute 1 * 2 * 3 * 4 * 5 * 6 = 720, which is returned to the main() function. */
#include<iostream>
using namespace std;
int factorial(int n);
int main()
{
int n;
cout << "Enter a positive integer: ";
cin >> n;
cout << "Factorial of " << n << " = " << factorial(n);
return 0;
}
int factorial(int n)
{
if(n > 1)
return n * factorial(n - 1);
else
return 1;
}
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